Commit 7ca5ca60 authored by Julia Lawall's avatar Julia Lawall Committed by Linus Torvalds

fs/autofs4: use memdup_user

Use memdup_user when user data is immediately copied into the allocated
region.  Elimination of the variable ads, which is no longer useful.

The semantic patch that makes this change is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression from,to,size,flag;
position p;
identifier l1,l2;
@@

-  to = \(kmalloc@p\|kzalloc@p\)(size,flag);
+  to = memdup_user(from,size);
   if (
-      to==NULL
+      IS_ERR(to)
                 || ...) {
   <+... when != goto l1;
-  -ENOMEM
+  PTR_ERR(to)
   ...+>
   }
-  if (copy_from_user(to, from, size) != 0) {
-    <+... when != goto l2;
-    -EFAULT
-    ...+>
-  }
// </smpl>
Signed-off-by: default avatarJulia Lawall <julia@diku.dk>
Cc: Ian Kent <raven@themaw.net>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent b81d67a5
...@@ -95,7 +95,7 @@ static int check_dev_ioctl_version(int cmd, struct autofs_dev_ioctl *param) ...@@ -95,7 +95,7 @@ static int check_dev_ioctl_version(int cmd, struct autofs_dev_ioctl *param)
*/ */
static struct autofs_dev_ioctl *copy_dev_ioctl(struct autofs_dev_ioctl __user *in) static struct autofs_dev_ioctl *copy_dev_ioctl(struct autofs_dev_ioctl __user *in)
{ {
struct autofs_dev_ioctl tmp, *ads; struct autofs_dev_ioctl tmp;
if (copy_from_user(&tmp, in, sizeof(tmp))) if (copy_from_user(&tmp, in, sizeof(tmp)))
return ERR_PTR(-EFAULT); return ERR_PTR(-EFAULT);
...@@ -103,16 +103,7 @@ static struct autofs_dev_ioctl *copy_dev_ioctl(struct autofs_dev_ioctl __user *i ...@@ -103,16 +103,7 @@ static struct autofs_dev_ioctl *copy_dev_ioctl(struct autofs_dev_ioctl __user *i
if (tmp.size < sizeof(tmp)) if (tmp.size < sizeof(tmp))
return ERR_PTR(-EINVAL); return ERR_PTR(-EINVAL);
ads = kmalloc(tmp.size, GFP_KERNEL); return memdup_user(in, tmp.size);
if (!ads)
return ERR_PTR(-ENOMEM);
if (copy_from_user(ads, in, tmp.size)) {
kfree(ads);
return ERR_PTR(-EFAULT);
}
return ads;
} }
static inline void free_dev_ioctl(struct autofs_dev_ioctl *param) static inline void free_dev_ioctl(struct autofs_dev_ioctl *param)
......
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